1. Field of the Invention
The invention relates in general to a light-emitting device, and more particularly to a light-emitting device having several air holes.
2. Description of the Related Art
Accompany with the increase in the awareness of environmental protection, light-emitting diode (LED) lamps have attracted people's attention and been widely used. LED lamps have the advantages of high luminous efficiency, low power consumption and long lifespan, and are capable of emitting color lights. LEDs generate heat during a luminescence process. In order to dissipate the heat generated by the LEDs, the lamp casing of an LED lamp is normally formed by a heat conductive material for effectively convecting the heat to the exterior.
As the brightness of LED increasing, conventional lamp casing is no longer applicable. Therefore, how to design a lamp casing having better heat dissipation efficiency has become a prominent task for the industries.